A pencil and watercolour drawing of a stretch of river seen beyond a towpath with a gate and trees. In the distance across the river is a mansion in a meadow bordered by trees. Several boats are on the river. On the horizon, several further buildings are indicated. Inscribed on the verso of the modern mount, 'Sion House', possibly copied from an earlier mount, or the back of the drawing.

The inscription is inaccurate, as the pedimented building does not resemble Syon House, home of the Duke of Northumberland in Middlesex. The drawing instead shows Marble Hill House, seen from the Richmond bank. The same subject, of 'the Thames at Twickenham' was often repeated by Richard Wilson, a friend of Sandby who collected many of Wilson's drawings.